As a process for treating waste materials comprising botanical tissues generated during rice growing, a wheat production, production of grain such as corn and sugarcane, or production of legumes, adopted has been a process wherein waste materials are incinerated in the fields; a process wherein waste materials are incinerated in an incinerator with fuel such as heavy oil or light oil; or a process wherein compost is prepared by mixing vegetable waste materials with sawdust, rice bran or the like and piling the resultant up. However, the process wherein waste materials are incinerated in an incinerator requires a large quantity of fuel and the cost of transportation, and it has been considered whether the process wherein waste materials are incinerated in the fields should be prohibited, because of a problem of environmental pollution caused by the generated soot and smoke (a rice-straw pollution). Concerning the process of composting vegetable waste materials, adopted have been a process comprising mixing straw, sawdust, rice bran or the like to vegetable waste materials, sprinkling the mixture with slaked lime, piling the resulting mixture up out in the open and thereby letting it decay naturally; and a process for preparing compost comprising mixing finely-crushed vegetable waste materials with sawdust, chaff, chicken droppings or the like, regulating moisture of the mixture, adding fermentative bacteria, treated compost or the like to the resultant and stirring the resulting mixture in a container and whereby fermentation is carried out. However, according as agriculture is modernized and mechanized, the process for preparing compost tends not to be performed because of both labor and a period of time required to make the mixture ripe. Therefore, such waste materials tend to become industrial waste though it is recognized as beneficial resources.
As a process other than those mentioned above, there is a process wherein vegetable waste materials are treated with microbiological preparation. Vegetable waste materials are difficult to dissolve because of the structure, which is caused mainly by cellulose and/or hemicellulose in the vegetable waste materials. Because of this, cellulose and/or hemicellulose need to be hydrolyzed at least partly at the first step so that the plant fibrous materials can be treated and then used beneficially. As a process for hydrolyzing cellulose and/or hemicellulose, known is a process for treating wherein agents for decomposing rice straw or the like comprising the mixture of many kinds of bacteria are used. In Japanese Unexamined Patent Publication No. 157285/1996, described is a process for preparing liquid compost from vegetable waste materials wherein at least one of pectin, cellulose and hemicellulose is decomposed with plant fibrous materials decomposing enzymes produced by fungi or bacteria. However, the process requires that a place for treatment should be obtained and provided with facilities for the treatment, so that labor to transport vegetable waste materials to the place is required. Furthermore, in Japanese Unexamined Patent Publication No. 2613/1995, described is a bacterial preparation for agriculture which is sprinkled directly to the fields. However, the decomposition of vegetable waste materials by using the agent takes a long time from sprinkling of the agent over the fields to observing the effect, especially to the resulting vegetable waste materials becoming ripe. The reason is that the vegetable waste materials are decomposed with plant fibrous materials decomposing enzymes which microorganisms produce after cultivation, i.e. that the decomposition of vegetable waste materials requires the multiplication of the bacteria in soil.
For the purpose of allowing the existing bacterial preparation and lime-nitrogen agents to work effectively in cold districts such as Tohoku and Hokkaido which are in a Japanese grain-growing district, it is insufficient to plow the agents in the fields once, so that it is necessary to do that twice. At the time of rice growing, waste materials which are not decomposed ferment after rice planting to generate gas, and whereby taking root of young plant and growth of the roots are inhibited.
It is an object of the present invention to provide a process for decomposing vegetable waste materials which solves problems such as the problem of treatment costs mentioned above, the problem of energy, an environmental problem and the problem of time for treatment which are difficult to be solved by prior art, without depending on living conditions of microorganisms and without the need to transport waste materials comprising plant fibrous materials.